This invention relates to fluorescent lamp adapters and, in particular, to a fluorescent lamp adapter for a residential incandescent-type lamp fixture.
It is well known that a fluorescent lamp lighting system is more efficient than an incandescent lamp lighting system by a factor of 3 to 4 or more for equivalent illumination. In the past, however, fluorescent lamps have not been used to any appreciable degree for indoor residential lighting because of their poor color rendering properties, as compared to incandescent lighting. In recent years, though, fluorescent lamps are available with both a high luminous output and a color appearance and color rendition comparable to incandescent. A number of adapters have been disclosed to convert residential incandescent lighting fixtures to fluorescent.
One such adapter is disclosed in U.S. Pat. No. 2,817,004 dated Dec. 17, 1957 issued to Baumgartner et al. This patent discloses a combined adapter and holder for circular tubular fluorescent lamps. The combined adapter and holder are mountable on existing light fixtures designed for incandescent lamps equipped with screw-type bases and with the plane of the circular lamp envelope being essentially vertical.
Another such lamp adapter is disclosed in U.S. Pat. No. 2,697,777 dated Dec. 21, 1954, issued to Ercole Rosa. This patent describes a lamp adapter comprising a body including a first section and a second section, a circumferential ring on the body is secured to the first section and second section, securing the first section to the second section. A plurality of circumferentially spaced grooves in the body and a plurality of brackets are included, the brackets have hook portions detachably engaged in the grooves between the ring and the body. The brackets have arcuate free-end portions adapted to support a circular fluorescent lamp.
In an Article appearing in Lighting Design and Application, March 1976 edition, entitled "Conversion of Incandescent Lamp Sockets to Fluorescent in the Home Market" by E. A. Dale, a retrofit lighting system for converting incandescent fixtures to fluorescent is described. In FIG. 5 of the Article is shown a solid-state ballast mounted within the periphery of the harp of a table lamp. A circular tubular fluorescent lamp is supported in a horizontal orientation around the harp.